PROJECT SUMMARY Autism Spectrum Disorder (ASD) is increasingly prevalent, affecting 1 in every 68 children in the United States. In addition to presenting children with pervasive social and behavioral challenges, ASD is also associated with profound deficits in perceiving a person's gaze. This basic impairment in visual perception is associated with social anxiety, impairments of joint attention, delayed language development, as well as difficulty understanding another person's mental state and engaging in reciprocal social interactions. Research on gaze perception among children with ASD is thus of great importance. Yet despite decades of work, understanding of the mechanisms of gaze perception in ASD is surprisingly incomplete. This is largely because investigations of gaze in ASD focus exclusively on perception of a person's eyes, ignoring the more nuanced ways in which gaze is typically seen, as a distinct combination of a person's head and eye rotation. This integrative process, which we refer to as emergent gaze, has been gaining traction in research with typical adults, yet consideration of emergent gaze is absent in current theories of gaze perception in ASD. This is surprising since this is precisely the kind of integrative visual process that may present challenges to children with ASD. The long-term goal of this proposal is to more completely understand how children with ASD perceive gaze, determining if they have the visual mechanisms to perceive gaze from the entire face, and if so, under which circumstances they are likely to use these mechanisms. Aim 1 of this proposal uses psychophysical methods to examine, for the first time, whether children with ASD differ from typically-developing children (TDs) in the way they integrate information across a face to perceive the gaze of a 2D person. In Aim 2, we propose to use a relatively new technology, socially-assistive robotics, to determine how children with ASD compare to TDs in terms of using emergent gaze when seeing a realistic 3D face. Pilot data suggest a surprising pair of outcomes?children with ASD see gaze like TDs and adults when evaluating 3D cues from a robot, but not when evaluating 2D images of a face. The basic work in this proposal is likely to have several broad, health-related impacts. First, this research should advance knowledge of visual mechanisms underlying social-perceptual deficits in ASD. Second, this proposal will directly connect the rapidly growing field of autism research with updated models of gaze representation already common among typical adults. Third, Aim 2 will lay the foundation for future research and interventions that utilize new technology to improve gaze perception in ASD. Last, this proposal will bring new research and interdepartmental collaboration to a growing University and support the integration and expansion of two successful community outreach programs. By examining how children with ASD interpret visual cues vital for social interaction, this proposal is squarely in line with the mission of the NICHD, particularly in terms of helping children to achieve their full potential for healthy productive lives.